Many of the healthy nutrients found in vegetables are fat-soluble (they dissolve in fat). Among these fat-loving health promoters are betacarotene, vitamin A, lutein, lycopene, and zeaxanthin. These nutrients are known as carotenoids and they lower the risk of developing diseases like cancer, heart disease, and macular degeneration. So the more of these fat-soluble nutrients you are able to absorb, the better off you are. Previous studies have shown that monounsaturated fats (extra virgin olive oil is your best choice) significantly boost levels of carotenoids in your bloodstream after eating a salad. Now a new study shows that eggs in your salad may have a similar effect.
It needs to be said at the outset that the new study was partly funded by the American Egg Board alongside the National Institute of Health and the Purdue Ingestive Behaviour Research Centre. So yes, you might suspect a bias from the researchers although we’d like to think that the researchers would be independent in their findings and they do make logical sense.
For the study subjects consumed a raw mixed vegetable salad with no eggs on one occasion, a salad with 1.5 eggs on another occasion, and a salad with three eggs on another occasion. All salads were served with three grams of canola oil. Canola oil is a source of monounsaturated fat but extra virgin olive oil is a far better option as a monounsaturated fat source. The process of making Canola oil involves a combination of high-temperature mechanical pressing and solvent extract, usually using hexane. Even after considerable refining, traces of the solvent remain. This and other processes involved in Canola oil manufacture can alter the omega-3 content in the oil and increase trans fats.
Given that canola oil was a constant in all three instances the results of the trial were designed to see if the presence of egg would change nutrient absorption. The egg used in this experiment was scrambled eggs (75 grams and 150 grams) to ensure that the participants consumed both egg yolk and egg whites.
The results showed that absorption of carotenoids was 3.8 times greater when the salad contained three eggs compared to no eggs. The researchers think it is the nutrients in the egg yolk that are facilitating carotenoid absorption. While egg yolks do contain carotenoids the absorption boost is greater than the carotenoids the eggs provide suggesting that other nutrients and fats found in the egg are helping the carotenoids get into your bloodstream. The researchers make the point that a large egg contains about 290 kilojoules while a comparable two tablespoons of salad dressing contains around 630 kilojoules.
Whether it be extra virgin olive oil or a free range egg, these additions can make sure that you get even more out of your salad.
